Dennis Rodman had the most games with 20+ rebounds, with 158 games.

who has the most 20 rebound games
Interpreted as:
Who has the most 20 or more rebound regular-season games?
RodmanDrummondHowardJordanBarkleyMutomboOlajuwonCambyWallaceWillisMaloneGarnettO'NealChandlerLaimbeerWhitesideWilliamsDuncanEwingOakleyCapelaWilliamsSeikaly15884826054524844423737363531302827262322212121
NAMEGPREBMPGPPGRPGAPGSPGBPGTPGFGMFGAFG%3PM3PA3P%FTMFTAFT%MINPTSASTSTLBLKTOVPF+/-
Dennis RodmanDennis Rodman1583,56840.68.022.62.50.70.72.13.36.847.70.20.730.81.32.356.16,4121,270398117113334504+249
Andre DrummondAndre Drummond841,83037.520.221.82.01.61.92.48.415.454.60.00.34.83.46.453.33,1501,697171135161200267+334
Dwight HowardDwight Howard821,78539.121.321.81.71.12.63.47.513.157.10.00.18.36.311.356.33,2101,74514094213278256+627
DeAndre JordanDeAndre Jordan601,27436.014.121.21.70.82.01.75.48.365.20.00.00.03.37.344.82,16184310345117100158+393
Charles BarkleyCharles Barkley541,18942.526.222.04.41.91.34.39.216.256.80.51.927.57.39.774.52,2951,41423910069233177+87
Dikembe MutomboDikembe Mutombo521,14341.813.722.01.40.54.22.84.58.752.10.00.00.04.66.670.02,1737127427217145151+111
Hakeem OlajuwonHakeem Olajuwon481,01940.926.921.22.62.44.23.710.620.651.30.00.10.05.88.567.51,9641,290125114203178190+35
Marcus CambyMarcus Camby4494638.011.921.53.01.13.31.94.810.745.30.00.211.12.23.366.41,6735241345014583123+241
Ben WallaceBen Wallace4291240.69.221.72.01.23.31.33.87.451.10.00.140.01.63.841.91,70538582501385693+334
Kevin WillisKevin Willis3781041.522.721.91.71.00.92.79.118.648.70.20.536.84.45.875.51,53584064383399114+14
Moses MaloneMoses Malone3780439.928.121.71.62.09.220.245.30.00.10.09.812.478.91,4771,041587497
Kevin GarnettKevin Garnett3677241.823.921.45.41.12.02.89.219.447.40.30.831.05.26.381.61,5048591953971102104+159
Shaquille O'NealShaquille O'Neal3576042.531.321.72.60.43.73.412.420.859.80.00.00.06.511.755.31,4891,0969014129118116+160
Tyson ChandlerTyson Chandler3167337.213.621.71.20.61.81.75.49.755.70.00.00.02.84.661.51,1544223719555279+244
Bill LaimbeerBill Laimbeer3064139.520.221.42.27.915.849.80.30.934.64.15.083.21,18660567111
Hassan WhitesideHassan Whiteside2860734.119.621.70.70.73.22.58.213.361.80.10.150.03.15.062.99545502019897175+152
Buck WilliamsBuck Williams2757243.420.421.22.01.57.714.055.10.00.04.97.267.71,171550544199
Tim DuncanTim Duncan2656442.225.421.73.10.83.13.29.520.047.80.10.333.36.29.565.21,0966608120808468+80
Patrick EwingPatrick Ewing2349641.027.321.63.21.23.83.310.420.850.00.00.133.36.59.072.39426287427887786+33
Charles OakleyCharles Oakley2248439.716.822.03.31.40.53.46.413.348.30.00.20.04.05.375.28733707330127586-2
Clint CapelaClint Capela2145736.319.421.81.10.92.31.38.412.965.60.00.02.64.755.17624082319482746+132
Jayson WilliamsJayson Williams2147238.914.222.51.40.71.02.15.313.539.40.00.10.03.55.563.88162982915224480+78
Rony SeikalyRony Seikaly2145341.520.621.61.70.71.53.57.515.648.30.00.150.05.58.266.58714323615317373
Kevin LoveKevin Love1942139.624.322.22.50.80.82.27.917.246.21.23.632.47.38.981.27524624815164236+69
DeMarcus CousinsDeMarcus Cousins1838140.330.621.24.91.42.14.411.322.849.40.92.932.17.110.070.67255508825377969+49
StatMuse has game-level data for rebounds going back to the 1982-83 season.

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